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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Liver Mass: An Unusual Presentation of Multiple Myeloma

Mhadgut, Hemendra, M.D., Mansurov, Alay, Zafar, Rabia, Krishnan, Koyamangalath 28 April 2020 (has links)
Multiple myeloma is characterized by proliferation of plasma cells in the bone marrow, producing monoclonal immunoglobulin. It accounts for 17% of hematologic malignancies in the US. Diagnosis is often suspected in the setting of bone lytic lesions, anemia, hypercalcemia or renal failure. Rarely, multiple myeloma can present with soft tissue involvement which can be difficult to diagnose. Below we present one such presentation. Our patient is a 53-year-old who was initially diagnosed with multiple myeloma six years back when he presented to hospital with back and right leg pain. On admission he was found to have multiple lytic lesions involving the appendicular and axial skeleton. On further workup, bone marrow biopsy showed 30% plasma cells with IgG kappa monoclonal protein elevation. Patient was diagnosed with ISS stage II multiple myeloma. He was treated with standard regimen with Velcade, Revlimid and dexamethasone with excellent response. Patient was evaluated for stem cell transplant however did not qualify for it due to social challenges. Patient was continued on maintenance therapy with Velcade and Revlimid for 8 cycles prior to clinical relapse with lytic lesions in the C-spine. At this point patient was switched to different therapeutic regimen with pomalidomide, carfilzomib and dexamethasone and had excellent response for 35 cycles on this regimen. Patient had interruption in treatment for 3 months due to other medical comorbidities. A repeat bone marrow biopsy which was done in November of 2019 revealed extensive bone marrow involvement with 70% plasma cells concerning for relapse. Patient was started on single agent daratumumab in December 2019 however had a difficult course interrupted by right-sided abdominal pain, persistent nausea and decreased appetite requiring hospital admission. Further workup revealed a 2.7 cm lesion in the liver as well as a 4.9 x 7.3 cm T11 left paraspinal soft tissue mass. Biopsy of the liver lesion revealed sheets of kappa restricted abnormal plasma cells concerning for progression of disease. Given the involvement of the visceral organ and the extent of his disease, it was decided to switch patient's treatment from single agent daratumumab to a multi agent chemotherapy regimen with dexamethasone, cyclophosphamide, etoposide and cisplatin. Patient received his 1st cycle inpatient and had marked symptomatic improvement and was discharged home. His M-protein spike reduced from 3.9 to 1.8 g/dl post once cycle of treatment. Soft tissue involvement by multiple myeloma is rare event. Though malignant plasma cells may diffusely infiltrate the liver parenchyma, the nodular spread is unique. In review by Talamo et al, out of 2,584 patients with MM, only 11 had liver plasmacytomas. This phenomenon is driven by lack of expression of adhesion molecules, increased heparanase-1 expression and loss of chemokine receptors on myeloma cells. Such alterations in cell architecture lead to more aggressive disease behavior. At present time treatment for this unique patient population does not differ from other MM cases. It is important for clinicians to recognize the possibility of such event.
22

Neonatal DSP-4 Treatment Modifies Antinociceptive Effects of the CB <sub>1</sub> Receptor Agonist Methanandamide in Adult Rats

Korossy-Mruk, Eva, Kuter, Katarzyna, Nowak, Przemysław, Szkilnik, Ryszard, Rykaczewska-Czerwinska, Monika, Kostrzewa, Richard M., Brus, Ryszard 01 January 2013 (has links)
To study the influence of the central noradrenergic system on antinociceptive effects mediated by the CB1-receptor agonist methanandamide, intact rats were contrasted with rats in which noradrenergic nerves were largely destroyed shortly after birth with the neurotoxin DSP-4 [N-(-2-chloroethyl)-N-ethyl-2-bromobenzylamine (50 mg/kg sc × 2, P1 and P3); zimelidine (10 mg/kg sc, 30 min pretreatment, selective serotonin reuptake inhibitor). When rats attained 10 weeks of age, monoamine and their metabolite concentrations were determined in the frontal cortex, thalamus, and spinal cord by an HPLC/ED method. Antinociceptive effects after methanandamide (10 mg/kg ip) apply were evaluated by a battery of tests. In addition, immunohistochemistry and densitometric analysis of the cannabinoid CB1 receptor in the rat brain was performed. DSP-4 lesioning was associated with a reduction in norepinephrine content of the frontal cortex (>90 %) and spinal cord (>80 %) with no changes in the thalamus. Neonatal DSP-4 treatment produced a significant reduction in the antinociceptive effect of methanandamide in the tail-immersion test, hot-plate test and writhing tests. In the paw pressure and formalin hind paw tests results were ambiguous. These findings indicate that the noradrenergic system exerts a prominent influence on analgesia acting via the cannabinoid system in brain, without directly altering CB1 receptor density in the brain.
23

Neonatal DSP-4 Treatment Modifies Antinociceptive Effects of the CB <sub>1</sub> Receptor Agonist Methanandamide in Adult Rats

Korossy-Mruk, Eva, Kuter, Katarzyna, Nowak, Przemysław, Szkilnik, Ryszard, Rykaczewska-Czerwinska, Monika, Kostrzewa, Richard M., Brus, Ryszard 01 January 2013 (has links)
To study the influence of the central noradrenergic system on antinociceptive effects mediated by the CB1-receptor agonist methanandamide, intact rats were contrasted with rats in which noradrenergic nerves were largely destroyed shortly after birth with the neurotoxin DSP-4 [N-(-2-chloroethyl)-N-ethyl-2-bromobenzylamine (50 mg/kg sc × 2, P1 and P3); zimelidine (10 mg/kg sc, 30 min pretreatment, selective serotonin reuptake inhibitor). When rats attained 10 weeks of age, monoamine and their metabolite concentrations were determined in the frontal cortex, thalamus, and spinal cord by an HPLC/ED method. Antinociceptive effects after methanandamide (10 mg/kg ip) apply were evaluated by a battery of tests. In addition, immunohistochemistry and densitometric analysis of the cannabinoid CB1 receptor in the rat brain was performed. DSP-4 lesioning was associated with a reduction in norepinephrine content of the frontal cortex (>90 %) and spinal cord (>80 %) with no changes in the thalamus. Neonatal DSP-4 treatment produced a significant reduction in the antinociceptive effect of methanandamide in the tail-immersion test, hot-plate test and writhing tests. In the paw pressure and formalin hind paw tests results were ambiguous. These findings indicate that the noradrenergic system exerts a prominent influence on analgesia acting via the cannabinoid system in brain, without directly altering CB1 receptor density in the brain.
24

Supersized Atheroma Causing Acquired Coarctation of Aorta Leading to Heart Failure

Karakattu, Sajin, Murtaza, Ghulam, Dinesh, Sharma, Sivagnanam, Kamesh, Schoondyke, Jeffrey, Paul, Timir 01 January 2017 (has links)
Calcified atheromatous aortic lesion causing significant narrowing of the aorta is an uncommon clinical entity. This calcified atheroma leads to obstruction of the lumen of the aorta simulating acquired coarctation of aorta causing impaired perfusion of lower limbs, visceral ischemia, and hypertension. We report a case of 58-year-old patient who presented with dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, 25-lb weight gain, lower extremity edema, and chest pain. Extensive workup including computed tomography and magnetic resonance imaging revealed a large calcific mass in the aortic arch causing his presenting symptoms. After surgical correction his symptoms resolved. Any patient presenting with heart failure symptoms in the setting of uncontrolled renovascular hypertension, intermittent claudication symptoms, or visceral ischemia with normal ejection fraction but moderate to severe left ventricular hypertrophy should be in high suspicion for acquired coarctation of aorta. The routine thorough examination of pulses in bilateral upper and lower extremities in all hypertensive patients is a very simple and useful clinical tool to diagnose acquired aortic coarctation.
25

MMP20 and ARMS2/HTRA1 are Associated with Neovascular Lesion Size in Age-Related Macular Degeneration / MMP20とARMS2/HTRA1は滲出型加齢黄斑変性の病変サイズと相関する

Akagi, Yumiko 25 January 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19404号 / 医博第4055号 / 新制||医||1012(附属図書館) / 32429 / 京都大学大学院医学研究科医学専攻 / (主査)教授 野田 亮, 教授 瀬原 淳子, 教授 藤渕 航 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
26

Automatic Segmentation and Classification of Multiple Sclerosis Lesions Using Quantitative Magnetic Resonance Imaging

Alfredsson, Johanna January 2019 (has links)
Multiple sclerosis is a neurological disease causing a degeneration of myelin around the axons in the central nervous system. This process leaves traces in the form of lesions, which can be distinguished in an MRI examination. It is important to detect these at an early stage to state diagnosis and initiate medication.  In this Master's Thesis, an automatic segmentation algorithm was developed, with the purpose of segmenting possible multiple sclerosis lesions. Secondly, a progression model was developed with the purpose of estimating the state of each individual lesion. The implementation was based on synthetic contrast weighted images, segmentation maps and quantitative relaxation maps produced by SyMRI (SyntheticMR, Linköping, Sweden). The automatic segmentation algorithm has a relatively high sensitivity but low precision, causing a large number of false positives. The algorithm performed better in the cerebrum compared to the cerebellum. The large number of false positives appeared mainly due to partial volume effects, creating hyperintense artifacts in synthetic T2W FLAIR images. A larger amount of data would have been desirable to create a more robust algorithm. The progression model showed promising results, with a clear correlation to the synthetic contrast-weighted images and segmentation maps available in SyMRI. The progression model could be useful in disease monitoring, medical decisions and diagnosis of Multiple Sclerosis.
27

Canine Platelet Concentrates: An In Vitro Study to Effectively Provide a Source of Functional Platelets

Sink, Carolyn A. 04 April 2002 (has links)
This study monitored the storage lesion of 15 units of canine platelet concentrates harvested by differential centrifugation. Canine platelet concentrates were stored at 20-24°C in a platelet rotator for a total of 9 days; the storage lesion of three second generation platelet storage containers was compared. The battery of in vitro tests used to monitor the storage lesion were selected from previous studies performed with human platelet concentrates separated by differential centrifugation. Based on these tests, canine platelet concentrates exhibited a storage lesion similar to human platelet concentrates. Metabolic analytes demonstrated decreasing pH, carbon dioxide, bicarbonate and glucose concentrations concurrent with increasing oxygen and lactate dehydrogenase activity over the 9-day period. Platelet structural changes were monitored by mean platelet volume, which began to increase on Day-5. Platelet function appeared to be compromised, as indicated by aggregation studies using collagen and adenosine diphosphate as agonists. Product sterility was maintained. There was no consensus of data supporting superior performance of one platelet storage container. This study indicates that canine platelet concentrates may be harvested by differential centrifugation of whole blood. In vitro studies utilizing three second-generation platelet storage bags support a previous study and concurs that canine platelet concentrates stored at 20-24°C using continuous agitation are viable for at least 5 days. / Master of Science
28

The Origin of the doppelgangers : A review of the neurological explanations of Capgras syndrome

Orostica, Sandra, Thorsell, Per January 2024 (has links)
At its core, Capgras syndrome is the delusional belief that someone close to you has been replaced by an identical imposter. Capgras has historically been explained with Freudian psychodynamic theories concerning latent hostility and a sense of personal or professional inadequacy. There is now widespread consensus in the scientific community that Capgras syndrome can arise from brain lesions. Various hypotheses have been proposed to explain its mechanism. The mirror-image-of-prosopagnosia hypothesis posits a disruption of the dorsal visual pathway. Another hypothesis emphasizes the role of a single lesion affecting the functional connectivity of the retrosplenial cortex. Our analysis of 10 case studies reveals inconsistencies with these hypotheses, particularly in accounting for the diverse lesion locations observed in Capgras patients. Our findings suggest that Capgras syndrome likely stems from a multifactorial aetiology involving neurological and neuropsychiatric factors. Lesions may impact multiple areas associated with facial processing and belief evaluation, challenging the notion of a single lesion explanation.
29

Reactivities Leading to Potential Chemical Repair of Sunlight-Induced DNA Damage: Mechanistic Studies of Cyclobutane Pyrimidine Dimer (CPD) Lesions under Alkaline Conditions

Ritu Chaturvedi (9760955) 07 January 2021 (has links)
<p>Cyclobutane pyrimidine dimers (CPD) are the predominant DNA lesions formed upon exposure of this biopolymer to sunlight. Given the potentially dire biological consequences of DNA lesions, there is a need to fully characterize their behaviour, with an eye towards understanding their complete reactivity and as a possible means to detect and quantify their presence in the genome. The work described in this dissertation describes studies of the alkaline reactivity of CPD lesions generated within dinucleotide & polynucleotide strands. It was found that CPD-TpT is generally inert under alkaline conditions at room temperature, which is in agreement with earlier studies on alkaline hydrolysis of CPD-thymine and CPD-thymidine. However, a re-evaluation of the same reaction in the presence of <sup>18</sup>O labelled water demonstrated that, similar to other UV-induced DNA lesions containing a saturated pyrimidine ring, CPD undergoes a water addition at the C4=O group of the nucleobase leading to the formation of a hemiaminal intermediate. This intermediate, however, does not lead to hydrolysis products and completely reverts to starting material under those same conditions. Moreover, the two C4=O groups present on 3′ and 5′-thymines in a CPD molecule show different chemical reactivities, with the 3′ C4=O group having greater affinity towards water addition as compared to the one on 5′ end, a fact reflected in different rates of exchange with the incoming nucleophile leading to the hemiaminal intermediate. The <sup>18</sup>O labelling reaction was also investigated in CPD lesions generated within oligonucleotides to probe the cause of asymmetry between the 3′ <i>vs</i> 5′ C4=O groups; ultimately, it was determined that the asymmetric reactivity observed to occur between the two C4=O groups was an intrinsic property of the CPD molecule and did not arise as a result of asymmetry in a dinucleotide setting.</p><p><br></p> <p>In addition to the above studies, during the course of the investigation of the nucleophilic reactivity of CPD, a chemical reaction was observed leading to what appeared to be the rapid and total chemical reversal of CPD lesions to the original TpT (thymine-thymine dinucleotide)! This “repair” reaction occurred when CPD reacted with hydrazine, and appears facilitated by an inert atmosphere under which it rapidly proceeds to completion at room temperature.</p><br>
30

A Theoretical Model of the Effect of Bone Defects on Anterior Shoulder Instability: A finite Element Approach

Walia, Piyush January 2010 (has links)
No description available.

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